Gray whale population drops by quarter off West Coast

SEATTLE (AP) — Researchers say the population of gray whales off the West Coast of the United States has fallen by nearly one-quarter since 2016, resembling a similar die-off two decades ago.

NOAA Fisheries reported Tuesday that surveys counted about 6,000 fewer migrating whales last winter, 21,000 as compared with 27,000 in 2016.

The agency declared an “unusual mortality event” in 2019 as dozens of gray whales washed up on Pacific Ocean beaches.

Scientists aren't sure what has been causing the die-off. But they believe that it is within the range of previous population fluctuations and that the number of whales may have exceeded what the environment can support.